====== ffprobe - Size ======

<code bash>
ffprobe -v error -select_streams v:0 -show_entries stream=size -of default=noprint_wrappers=1:nokey=1 "input.mp4"
</code>

----

===== For MKV files =====

Some file format, such as .mkv, do not have size in the stream section.

<code bash>
ffprobe -v error -select_streams v:$i -show_entries format=size -of default=noprint_wrappers=1:nokey=1 "input.mkv"
</code>

----

===== Perform a null mux (FAST) - Video =====

<code bash>
ffmpeg -i "input.mkv" -map :v:0 -c copy -f null -
</code>

returns:

<code>
...
video:267625kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown
size=N/A time=00:23:37.70 bitrate=N/A speed=1.64e+03x    
</code>

<WRAP info>
**NOTE:**  This maps only the first video stream, and using a copy means it it super quick.
</WRAP>

----

===== Perform a null mux - Audio (FAST) =====

<code bash>
ffmpeg -i "input.mkv" -map a:0 -c copy -f null -
</code>

returns:

<code>
...
video:0kB audio:21408kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown
size=N/A time=00:23:37.69 bitrate=N/A speed= 938x   
</code>

<WRAP info>
**NOTE:**  This maps only the first audio stream, and using a copy means it it super quick.
</WRAP>

----

===== Perform a null mux (SLOW) =====

<code bash>
ffmpeg -i input -map 0:a:0 -c copy -f null -
</code>

returns:

<code>
...
video:15934kB audio:244224kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown
frame=33992 fps=1561 q=-0.0 Lsize=N/A time=00:23:37.70 bitrate=N/A speed=65.1x
</code>

<WRAP info>
**NOTE:**  The final readout will have that info.
</WRAP>

----